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Last February I moved into a recently extended Victorian house with some original single skin brick walls around the master bedroom on the first floor and the living room on the ground floor.
I recently noticed some mould on the wall in the master bedroom, in the outer corner most exposed to rain. I spotted a gap in the skirting board so naively put it down to that, put some expanding foam in there, gave everything a go with anti-mould spray and thought job done.
I looked at it this morning however (after a lot more rain) and noticed that the wall in that corner was wet to the touch. This is only in that corner, and only happening in the bedroom and not in the living room underneath. As this only seems to be happening after a month or two of seemingly endless rain I'm assuming that the bricks on this corner of the house have become saturated and the water is penetrating through.
Is this possible? And if so, would something like StormDry be a sensible approach to dealing with it or should I be looking elsewhere? The gutters and drainpipes look fine but I need to stand outside and check in a proper downpour to be sure.
I bet it's condensation on the inside not water from outside.
We had water on walls and mould in our 1920's house through Nov and Dec - we bought a good dehumidifier before Xmas and the moisture has completely gone.
It's taking litres out of the atmosphere every day.
Like you we moved into our new house in April but it had been modernised with new windows and probably been sealed too well. Our previous 1900's house was a draughty old hole and suffered no condensation issues!
It could be water penetrating the bricks, especially if the wind is driving it in. Our house bricks are like sponges and the water flows through them. We've got a cavity to keep it out though. I'd try sealing the outside of the bricks first, relatively cheap and easy to do, worked quite well on my garage.
We got damp in one of the bedrooms in our old house (solid brick walls but w bricks thick). The reason was a gutter overflowing and dripping down the wall where one gutter fed into another. The roofer found it with the aid of a hospipe as it wasn't obvious and needed a larger gutter fitting to solve it. That would be my first to check.
Our neighbour who lived 2 doors up had a gutter block an lift all the paint off in their newly decorated kitchen. They were gutted.
Could be water getting in or condensation if it's a cold spot in the room. If it is coming in then there should be a reason for it, like a knackered gutter or it needs re-pointing (with suitably breathable grout).
Having said that, I'd not go back to living in a single brick skin house without a dehumidifier.
A few thoughts that come after living in an old hovel for 12 years...
- condensation, as above. I remember the year we moved in we had a load of people round and i boiled a massive gammon joint on the hob. Went upstairs just before serving, and the walls (9" solid brick) had water running down then.
- water penetration from leaking guttering etc.
- are there gaps between the bricks on the vertical? There were in ours! Clay is plentiful round here, lime not soon much, so they just didn't bother on some of the verticals...
- it's not rising damp.
Is the house rendered with modern waterproof render, or painted with waterproof paint?
Don't cover the outside in some waterproofing stuff. The bricks need to breathe.
Had a single skin brick garage in our last house that leaked like crazy in driving rain. Water would just fall through it on the windward side and pool on the ground inside the structure. Waited for a really dry spell to dry the bricks out thoroughly then sprayed the outside with thompsons water seal. Problem went away.
Don’t cover the outside in some waterproofing stuff. The bricks need to breathe.
Don't you leave the inside untreated to allow them to breathe? So long as they're properly dried out before treatment it shouldn't be an issue = particularly if the plaster and wall covering on the inside is breathable in some way.
+1 gutters, flashings, downpipes etc
Alrighty, so step one is get a dehumidifier. Step two is check gutters and things once it's properly raining again. And then once life has dried out a bit and depending on how steps one and two have gone, maybe consider sealing the bricks with something like Thompsons water seal.
I can believe it's the coldest spot in the room as it's the most exposed wall and I can believe it's internal condensation because there are currently two adults and one 4 month old sleeping in that room. All the downpipes and things were moved and re-done when the extension was done and they all look pretty new so hopefully not those but we shall see!
If there's a significant amount of water running down the walls it's likely to find a way in. My grandmother had a single-skin brick corner that got very damp. It had cement harling on the outside (a common mistake dating back decades), that had cracked and/or also failing gutter above. We sold anyway without trying to remedy so can't be quite sure as to the root cause.
Avoid Thomson's waterseal at all cost or your bricks may look like they've been polished with Japanese car polish with lots of beading but even more problems
If there is no harling/ render the bricks will get saturated and then run down the inside but if it's only happening in a localised spot rather than all over the wall probably be a chocked downpipe /
gutter
One other reason why a 4" single brick is only fit for a coal shed
The front of the house has some sort of white render on it (not particularly modern) on the first floor. This covers one of the walls that make up the offending corner, while the other wall is just brick. From a lay mans 'standing outside and looking at it' approach it looks fine but I am no expert. Same goes for the condition of the pointing, no obvious gaps or gaping holes.
I'm pretty sure it's not rising damp as the room below is absolutely fine. I can also see the dpc doing its thing at the ground floor level.
If there is no harling/ render the bricks will get saturated and then run down the inside but if it’s only happening in a localised spot rather than all over the wall
The whole wall is noticeably cold to the touch and a couple of pictures hung on it started to have the mounts bend inside the frames. It's just this one most exposed corner where it's really going to town though (this is the part of the wall that's basically unshielded from the prevailing wind/rain direction by the house next door which is set back a bit).
Stormdry is breathable and is worth a try, and hopefully stops things getting worse.
With a situation where it's not obvious if it's damp coming in through the wall or condensation. It's an idea to fix a bit of aluminum foil, or aluminum tape, to the wall in the affected area. If it's condensation, then there will be water condensing on the foil and you can see it. If it's water coming through the wall the foil will appear dry on the side that you can see, with the surrounding area being damp .
Condensation is quite likely, we had it at the top of the bedroom walls even with a cavity wall with thermal blocks as the inner leaf. When it was freezing outside, a surface thermometer showed the temperature dropping off sharply towards the corner; I assume the cavity insulation has settled a bit. So I would be surprised if you didn't get it on a single skin wall.
There's a render on one wall of the corner? I'd check the render hasn't blown on the corner or above and isn't trapping water against the wall in a certain spot. The path of least resistance will presumably be to track back through the brick, rather than out through the render.
Either that or dodgy/missing pointing. On our house it's always dodgy pointing.....
Got a dehumidifier arriving tomorrow so hopefully that’ll do the job. After that I know where to start looking, so thanks all.
Is it possible to be running between render and brick?
I have exactly this issue in my edwardian house, a recessed cupboard in the bedroom (press in scotland) has a single brick leaf to the rear that is straight onto the gable, north east facing so is the coldest part of the house. When we refurbed it i added 25mm insulation behind the p'board but this has clearly not been enough as we are getting significant condensation there. The wall is rendered externally (recently too) but we still get damp patches in heavy rain, roof was repaired(?) a couple of years ago too.
I'll tell you what i'm doing as it might help or not??
I have a different roofer (known to me) coming to check the roof and lead flashings in this part of the roof to make sure there are no issues from the roof area FIRST.
I will then strip out the recess removing the plasterboard, 25mm insulation. re-frame the back of the recess leaving a cavity 50mm, then adding insulation between framing, and insulated p'board to the internal side, there will also be a vapour barrier. This should remove the cold spot and condensation issue permanently.
If you can you might want to consider lining the single skin walls as above if you can or have the internal space to do so but if you do get proper advice from a construction professional to decide on best resolution.
Avoid "waterproof" coatings for the brickwork, they won't last and will likely increase not decrease the condensation issue
https://www.thompsonsweatherproofing.co.uk/waterproofing/
This stuffs fantastic.
Cheap enough, and you can apply it with a weed spray bottle, so only takes a few minutes.
The water Beads off our brick shed, 4 years after application.
It does leave the bricks slightly shiny,so would caution using it in a "patch".
If youre getting damp in one spot, do you need to look at the pointing?
condensation
is absolutely our experience
single skin, exposed corner, cold to touch, often damp to the touch
if we run the stove in that room, the problem mostly goes away
a dehumidifier might well be a good fix